ch

Algorithms for Image Processing and Computer Vision Source Code

@c ----------------------------------------------------------------------
@node chdir, file system
@heading @code{chdir}
@subheading Syntax

@example
#include <osfcn.h>

int chdir(const char *new_directory);
@end example

@subheading Description

This function changes the current directory to @var{new_directory}.  If
a drive letter is specified, the current directory for that drive is
changed, else the current drive is changed. 

@subheading Return Value

Zero if the new directory exists, else nonzero and @var{errno} set if error.

@subheading Example

@example
if (chdir("/tmp"))
  perror("/tmp");
@end example

@c ----------------------------------------------------------------------
@node chmod, file system
@heading @code{chmod}
@subheading Syntax

@example
#include <osfcn.h>

int chmod(const char *filename, int mode);
@end example

@subheading Description

This function changes the mode (writable or write-only) of the specified
file.  The value of @var{mode} can be a combination of one or more of
the following:

@table @code

@item S_IREAD

Make the file readable

@item S_IWRITE

Make the file writable

@end table

@subheading Return Value

Zero if the file exists and the mode was changed, else nonzero. 

@subheading Example

@example
chmod("/tmp/dj.dat", S_IWRITE|S_IREAD);
@end example

@c ----------------------------------------------------------------------
@node chown, unix
@heading @code{chown}
@subheading Syntax

@example
#include <osfcn.h>

int chown(const char *file, int owner, int group);
@end example

@subheading Description

This function does nothing under MS-DOS

@subheading Return Value

This function always returns zero.